The clear advantages that the multidirectional propulsion system has over the current means for propulsion and maneuvering ships are known and described in document ES 2319149 A1 of the same applicant. Specifically, the invention described in document ES 2319149 A1 is characterized by pursuing two main objectives such as: increasing the propulsion efficiency and improving the maneuverability of ships.
In general, in order to increase the propulsion efficiency, said document provides a mechanism formed by a connecting rod crank-type drive system that moves a main oscillating axis; integral with said axis are the swing frame (structure that supports the blades) and the blades. When the axis (which is perpendicular to the surface of still water) rotates, drags the blades that are responsible for exerting the propulsion force that moves the ship.
As for improving the maneuverability of the ship a multidirectional connecting mechanism is described, which consists of a sling and other driving disc and an additional mechanism which is responsible for separating both discs, rotating the axis in the desired direction and reassembling the two discs. In this way the blades can be oriented in the desired direction, from 0° to 360°.
This invention substantially improves in the previous development, both in the way of generating the propulsion force and in the direction thereof with respect to the ship, by introducing a number of essential elements described below.
There are other documents as U.S. Pat. No. 272,949 (Augustus M. Freeman, 1883), which shows an oscillating propulsion system based on double set of pivoting fins mounted on “swing frames” that rotate alternately, in an oscillatory or reciprocating motion, about the same vertical axis to produce the effort force. However, this boat is a type of hand-propelled boat, which for construction issues, does not have the possibility of adapting to any mechanical propulsion or multidirectional connection mechanism.
As for the propulsion system, without the structure and swing frames and blades of the invention, the document U.S. Pat. No. 6,193,466 describes a propeller system based on blades that rotate in opposite directions jointly connected to two coaxial vertical shafts moved by transmission gears. In this case the movement performed by the axes is not alternating like that of the presented invention, with a minimum and a maximum sweep angle, but it is circular (360°), so that the speed cannot be adjusted by regulating the range of the sweep angle of the blades. Additionally, in this document the push orientation mechanism or govern mechanism is driven by a rudder tiller.
As for the multidirectional connection mechanism, document U.S. Pat. No. 2,573,382 shows a gear reverse mechanism, i.e. it changes its orientation but only in two positions 0° or 180°. This mechanism has the disadvantage of not allowing maneuvering, for example, at a dock.
Document WO2005/047100 shows a way of varying the direction of the boat but using a system different from that of the invention and which could not be adapted to the propulsion type of our ship, since in this case what is varied is the attack angle of each blade, which are mounted on an endless chain.
Document U.S. Pat. No. 975,972 proposes a set of three propellers (one central and two laterals) using two concentric shafts but with full rotations (not oscillating) and proposes a drive system different from that of the invention claimed here (it is not hypocycloid) with a multidirection not applicable to a single propulsion line.
Document U.S. Pat. No. 4,568,290 proposes the use of two oscillating, non-concentric shafts for the propulsion. The multidirection is not so by not being able to take turns of 360° on the horizontal plane.
Thus, none of the documents found by the applicant discloses a system for motor ships that has a propulsion and, at the same time, a rotation equipment, which solve together the problems found in the developments so far known and having a proven efficiency much higher than that of systems currently existing.